Reciprocal stabilization of ABL and TAZ regulates osteoblastogenesis through transcription factor RUNX2
Yoshinori Matsumoto, … , Ann Marie Pendergast, Robert Rottapel
Yoshinori Matsumoto, … , Ann Marie Pendergast, Robert Rottapel
Published October 31, 2016
Citation Information: J Clin Invest. 2016;126(12):4482-4496. https://doi.org/10.1172/JCI87802.
View: Text | PDF
Research Article Bone Biology Cell biology

Reciprocal stabilization of ABL and TAZ regulates osteoblastogenesis through transcription factor RUNX2

Abstract

Cellular identity in metazoan organisms is frequently established through lineage-specifying transcription factors, which control their own expression through transcriptional positive feedback, while antagonizing the developmental networks of competing lineages. Here, we have uncovered a distinct positive feedback loop that arises from the reciprocal stabilization of the tyrosine kinase ABL and the transcriptional coactivator TAZ. Moreover, we determined that this loop is required for osteoblast differentiation and embryonic skeletal formation. ABL potentiated the assembly and activation of the RUNX2-TAZ master transcription factor complex that is required for osteoblastogenesis, while antagonizing PPARγ-mediated adipogenesis. ABL also enhanced TAZ nuclear localization and the formation of the TAZ-TEAD complex that is required for osteoblast expansion. Last, we have provided genetic data showing that regulation of the ABL-TAZ amplification loop lies downstream of the adaptor protein 3BP2, which is mutated in the craniofacial dysmorphia syndrome cherubism. Our study demonstrates an interplay between ABL and TAZ that controls the mesenchymal maturation program toward the osteoblast lineage and is mechanistically distinct from the established model of lineage-specific maturation.

Authors

Yoshinori Matsumoto, Jose La Rose, Oliver A. Kent, Melany J. Wagner, Masahiro Narimatsu, Aaron D. Levy, Mitchell H. Omar, Jiefei Tong, Jonathan R. Krieger, Emily Riggs, Yaryna Storozhuk, Julia Pasquale, Manuela Ventura, Behzad Yeganeh, Martin Post, Michael F. Moran, Marc D. Grynpas, Jeffrey L. Wrana, Giulio Superti-Furga, Anthony J. Koleske, Ann Marie Pendergast, Robert Rottapel

×

Figure 5

ABL stabilizes the TAZ-TEAD complex required for osteoblast expansion.

Options: View larger image (or click on image) Download as PowerPoint
ABL stabilizes the TAZ-TEAD complex required for osteoblast expansion. (...
(A) HEK293T cells were cotransfected with GFP-TAZ (WT or S89A), with or without ABL (PP or KD), and stained by immunofluorescence. Scale bars: 10 μm. The images of intracellular TAZ (green) and nuclei (blue) are representative of 3 independent experiments. (B) HEK293T cells were cotransfected with Flag-TAZ and Myc-TEAD1, with or without ABL (PP or KD). The nuclear compartment was extracted from the cells, and Myc-TEAD1 immune complexes were probed with an anti-Flag antibody. (C) qPCR analysis of Ctgf mRNA expression in HEK293T cells cotransfected with TAZ, with or without ABL (PP or KD). n = 3. (D) qPCR analysis of Ctgf mRNA expression in MC3T3 cells infected with shGFP or shAbL, with or without a retroviral vector expressing TAZ (S89A). n = 3. (E) Growth curves of MC3T3 cells infected with shGFP or shABL, with or without a retroviral expressing TAZ (S89A), and cultured for 3 days. n = 3. (F) HEK293T cells were cotransfected with Flag-TAZ, with or without ABL (PP or KD). Flag-TAZ immune complexes were probed with an anti–p-YAP (Ser127) or anti–14-3-3 antibody. (G) HEK293T cells were cotransfected with Flag-TAZ and PP1α, with or without ABL (PP or KD). Flag-TAZ immune complexes were probed with an anti-PP1α antibody. (H) HEK293T cells cotransfected with Flag-TAZ, with or without ABL (PP), were cultured for 4 hours in the presence or absence of okadaic acid (100 nM). Flag-TAZ immune complexes were probed with an anti–p-YAP (Ser127) or anti–14-3-3 antibody. *P < 0.05, by ANOVA with a Tukey-Kramer post-hoc test. Data represent the mean ± SEM.